It is established that Castle was rejected by twenty-one other publishers before his first novel, "In a Hail of Bullets", was published by Black Pawn.
When at the cryogenic facility Castle asks Dr. Weiss if Ted Williams is there. Williams, considered by many to be the best hitter in baseball history, was the subject of this very issue about ten years before this aired. After Williams died, his son had this procedure done to preserve his head in the hopes of someday being able to revive him. Williams' daughter filed a lawsuit against the brother, and engaged in a public campaign to have him cremated, claiming that that was what Williams really wanted done with his remains. In the end the son won the case and his head was frozen.
One of the characters has the last name of 'Peck'. Either this is a coincidence or it is a nod to 'Walter Peck' (the EPA agent from Ghostbusters (1984)) who was played by William Atherton, who plays Dr Ari Weiss in this episode